Database

Hi all. I have two tables in access (VB6): SupplierInvoices & Sales. They both have 3 common field names: Date, Code & Qty. I need to query both tables via SQL query by a specific date range as follows (I know this is wrong, but just to give you an idea):

I could tell you what is not working here but you will find out much more if you read, understand than methodically practise what you have read and understood rather than throwing things together hoping they will work then asking for help when they don't work.

What the heck, I will tell you anyway - either change ITotal to sTotal or change sTotal to ITotal.
The column names for the unioned results need to be the same.

As an aside - I don't think that query is going to give you any information that is of any use as you are basically listing sales totals and dates together with invoice totals and dates with no ability to distinguish between what is a sales row and what is an invoice row.

I think you need to step away from the computer, read a book, follow tutorials and work out what you want to do on paper before typing SQL queries that you hope will somehow work.

“That which can be asserted without evidence, can be dismissed without evidence.”

Ok there is something REALLY wrong with this. You are trying to learn SQL using the absolutely WRONG tools. As I said VB6 is dead, you will not get anything but bad memories from old farts who used to use it.

Access is not a suitable learning platform for SQL it has some weird stuff unique to Access. Port your database to SQL Server (there is a clear migration path) and use the proper tools to learn TSQL.

You are doing yourself a disservice continuing to use these tools as you will need to UNLEARN a lot of stuff. Besides there are a huge number of resources to help you with the current tool sets.

Never underestimate the power of human stupidity -
RAH
I'm old. I know stuff - JSOP

Excellent points.
I learnt SQL using Access and basically I learnt nothing of use.

Then when I picked up SQL Server and did the training courses, the world of SQL open up to me with its resplendent unicorn rainbows and... okay I am exaggerating a bit but I think you make some very good points in your comment.

“That which can be asserted without evidence, can be dismissed without evidence.”

Have a look at my other comment where I explain what is going on.
I'd also suggest that you get into the habit of formatting your SQL so that is is easier to read.
Here's an example of a possible way of formatting your SQL:

In Access I want to group and assign data according to conditions with 2 values 0 and 1 (true or false) and with the condition NGAYGIAO>= #01/01/2019# and NGAYGIAO <=# 31/01/2019# me How to write commands ? The data I put in the excel file consists of two sheets: Original data and Result, where Original data is the original data sheet that is the result of the problem I need, when running the access issue, ask you to help me with the problem. http://www.mediafire.com/file/hkkw519bw2k3o9h/baitap_data2.xls/file

from the original data I created the result, if the contract in the month has LOAIHD = "FBAN" and between (#01/01/2019# and #31/01/2019#) then [BOOL] = 1 else [BOOL = 0, I will describe the condition of [BOOL] in C# code

from the original data I created the result, if the contract in the month has LOAIHD = "FBAN" and between (#01/01/2019# and #31/01/2019#) then [BOOL] = 1 else [BOOL = 0, I will describe the condition of [BOOL] in C# code

I had SQL Remote Connections working on a clien't server. For some reason I can no longer connect.

I'm getting

A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) (Microsoft SQL Server, Error: 53)
The network path was not found

I can remote into their server, I just can't connect to the DB either with SSMS or through my app. The ports are open, and SQL is configured for remote access.

I've tried all the usual debugging techniques, like this, but I can't get in.

Anyone have any other ideas?

If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.